Method and device for generating a nuclear magnetic resonance spectrum of nuclear spin moments of a sample

Abstract

A method for generating a nuclear magnetic resonance spectrum of nuclear spin moments of a sample includes a static magnetic field permeating the sample, and a detection spin moment with a detection region surrounding the latter. The detection region extends at least partly into the sample. The method also includes an antenna element for radiating in frequency pulses for influencing the nuclear spin moments and radio-frequency pulses for influencing the detection spin moment, where a polarization step involves polarizing at least one portion of the nuclear spin moments along the magnetic field to form a longitudinal magnetization, where a transfer step involves converting the longitudinal magnetization (M x ) into a transverse magnetization (M xy ) by radiating in a frequency pulse (F) with a 90° flip angle, wherein a detection step involves radiating in a sequence of radio-frequency pulses onto the detection spin moment and subsequently detecting a signal ( 32 ′) of the transverse magnetization (M xy ) present in the detection region and storing the signal as detection result in a list. The detection step is carried out a number of times repeatedly in succession, wherein the polarization step and the transfer step and also the detection steps are carried out.

The invention claimed is: 
     
       1. A method for generating a nuclear magnetic resonance spectrum of nuclear spin moments of a sample, using a static magnetic field permeating the sample, a detection spin moment which is an electron spin moment, said detection spin moment having a detection region surrounding the sample, and said detection region extending at least partly into the sample, and also an antenna element for radiating in frequency pulses for influencing the nuclear spin moments and radio-frequency pulses for influencing the detection spin moment, the method comprising:
 a polarization operation including polarizing a portion of the nuclear spin moments along the magnetic field to form a longitudinal magnetization, the portion being at least 1% of the nuclear spin moments; 
 a transfer operation including converting the longitudinal magnetization into a transverse magnetization by radiating in a frequency pulse; 
 a detection operation including:
 radiating a sequence of radiofrequency pulses onto the detection spin moment, 
 detecting a signal of the transverse magnetization present in the detection region, storing the detected signal as detection result, and 
 wherein the detection operation is carried out a number of times repeatedly in succession; 
 
 wherein the polarization operation, the transfer operation, and the detection operations are carried out repeatedly until a predefined number of repetitions is reached; 
 wherein the detection results are stored with each repetition; and 
 an evaluation operation including jointly evaluating the detection results across all repetitions. 
 
     
     
       2. The method of  claim 1 , wherein the detection spin moment is formed by an electron spin moment of a color center of a solid in contact with the sample. 
     
     
       3. The method of  claim 1 , wherein the nuclear spin moments are polarized with polarization spin moments of the solid. 
     
     
       4. The method of  claim 1 , wherein the sequence comprises a decoupling sequence for the detection spin moment. 
     
     
       5. The method of  claim 4 , wherein the decoupling sequence comprises:
 a first radio-frequency pulse configured to induce a 90° nuclear spin moment flip along a first pulse axis; 
 a second radio-frequency pulse configured to induce a 90° nuclear spin moment flip along a second pulse axis, the second pulse axis oriented perpendicularly to the first pulse axis; and 
 a number of third radio-frequency pulses, the third radio-frequency pulses provided between the first radio-frequency pulse and the second radio-frequency pulse, each of the third radio-frequency pulses configured to induce a 180° nuclear spin moment flip along one of two pulse axes oriented perpendicularly to one another; and 
 wherein one or more pulse spacings between the first, second, and third radiofrequency pulses are adapted to a precession frequency of the nuclear spin moments in the magnetic field. 
 
     
     
       6. The method of  claim 1 , wherein the evaluation operation includes summing or averaging the detection results across the repetitions point-by-point to generate second detection results. 
     
     
       7. The method of  claim 6 , wherein the evaluation operation includes autocorrelating and Fourier-transforming the second detection results. 
     
     
       8. The method of  claim 6 , wherein the evaluation operation includes updating the second detection results using Bayesian inference. 
     
     
       9. The method of  claim 1 , wherein each detection operation includes detection of signals corresponding to multiple differing detection spin moments. 
     
     
       10. The device of  claim 1 , wherein the detection spin moment is formed by an electron spin moment of a color center of a solid in contact with the sample. 
     
     
       11. A device for generating a nuclear magnetic resonance spectrum of nuclear spin moments of a sample, the device comprising:
 a magnet for generating a static magnetic field; 
 a solid with at least one integrated detection spin moment which is an electron spin moment; 
 an antenna element; and 
 a controller configured to cause the device to perform operations including: 
 a polarization operation including polarizing at least one portion of the nuclear spin moments along the magnetic field to form a longitudinal magnetization, the portion being at least 1% of the nuclear spin moments; 
 a transfer operation including converting the longitudinal magnetization into a transverse magnetization by radiating in a frequency pulse; 
 a detection operation including:
 radiating a sequence of radiofrequency pulses onto the detection spin moment, 
 detecting a signal of the transverse magnetization present in the detection region, 
 storing the detected signal as detection result, and 
 wherein the detection operation is carried out a number of times repeatedly in succession; 
 
 wherein the polarization operation, the transfer operation, and the detection operations are carried out repeatedly until a predefined number of repetitions is reached; 
 wherein the detection results are stored with each repetition; and 
 an evaluation operation including jointly evaluating the detection results across all repetitions. 
 
     
     
       12. The device of  claim 11 , wherein the or each the detection spin moment is arranged in the region of a nanostructuring introduced into the solid. 
     
     
       13. The device of  claim 11 , wherein the nuclear spin moments are polarized with polarization spin moments of the solid. 
     
     
       14. The device of  claim 11 , wherein the sequence comprises a decoupling sequence for the detection spin moment. 
     
     
       15. The device of  claim 14 , wherein the decoupling sequence comprises:
 a first radio-frequency pulse configured to induce a 90° nuclear spin moment flip along a first pulse axis; 
 a second radio-frequency pulse configured to induce a 90° nuclear spin moment flip along a second pulse axis, the second pulse axis oriented perpendicularly to the first pulse axis; and 
 a number of third radio-frequency pulses, the third radio-frequency pulses provided between the first radio-frequency pulse and the second radio-frequency pulse, each of the third radio-frequency pulses configured to induce a 180° nuclear spin moment flip along one of two pulse axes oriented perpendicularly to one another; and 
 wherein one or more pulse spacings between the first, second, and third radiofrequency pulses are adapted to a precession frequency of the nuclear spin moments in the magnetic field. 
 
     
     
       16. The device of  claim 11 , wherein the evaluation operation includes summing or averaging the detection results across the repetitions point-by-point to generate second detection results. 
     
     
       17. The device of  claim 16 , wherein the evaluation operation includes autocorrelating and Fourier-transforming the second detection results. 
     
     
       18. The device of  claim 16 , wherein the evaluation operation includes updating the second detection results using Bayesian inference. 
     
     
       19. The device of  claim 11 , wherein each detection operation includes detection of signals corresponding to multiple differing detection spin moments.